Those papers were published by the Audio Engineering Society in 2009 at the inaugural Audio For Games conference which I helped to organise following a conversation with Mike Kelly at GDC a couple of years before. Another contributor then and now is Dr. Damian Murphy of the University of York; some fruits of our 3D audio research collaboration are on the OpenAir soundfield website created by Dr. Simon Shelley, and in this paper published at the Swedish SMAC conference in summer 2013:
3D auralisation of vehicle sounds